The dispersion problem and the reflection wave problem in the pulse wire method

Yuhsiang Chang^1*, Chih-Wei Chen¹, Hsiung Chen¹, Ting-Yi Chung¹

¹Magnet group, National Synchrotron Radiation Research Center(NSRRC)), Hsinchu, Taiwan

* Presenter:Yuhsiang Chang, email:index0192@gmail.com

The pulse wire method is a very promising way for the first integral measurement of insertion devices. However, the dispersive nature of propagating waves in a wire limits the length of insertion devices. This problem can be solved by studying dispersion property of the wire and performing Fourier transformation on measuring data. In the other side, when the wire length is highly constrained by limited space, for example the space of a in-vacuum type insertion device, the reflecting waves overlap with the main signal causes extra errors in the measurement. This problem can be solved by installing oil dampers or analyzing the mixing wave data carefully.

Keywords: insertion device, first integral, pulse wire method, dispersion, damping